Impact of coating and indoor relative humidity on the deformation characteristics of the timber hybrid window frame

While the timber hybrid window is regarded as an alternative type of window for its durability and environmental benefits, moisture-related concerns caused by improper indoor humidity management in airtight buildings still remain. The long-term moisture performance of coated and non-coated timber hybrid window frames was evaluated through cyclic humidity tests of (90 and 30) % relative humidity in laboratory settings. During tests, the average shrinkage rate of the frame with coatings was 54.5% that of the frame without coating. The results show significantly reduced surface defects and improved dimensional stability on the coated frame.